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Current time:0:00Total duration:7:37

Video transcript

a pacemaker is a small device that helps the heart maintain an adequate or normal heart rate sometimes hearts beat too slowly and this is known as bradycardia again bradycardia means the heart's beating too slowly and this could be because either the hearts and a pacemaker isn't firing fast enough or because there is some sort of abnormal block in the hearts conduction system which causes the heart to beat too slowly and classically pacemakers are used to speed up slow heart rates or to speed up part rates that are braided kartik less commonly pacemakers are used to slow down fast heart rates and the medical term for a fast heart rate is tachycardia again this is less common most of the time pacemakers are used to speed up slow or bradycardia cards some pacemakers can even cordin a contraction between two chambers such as the ventricles so the pacemaker would ensure that the ventricles contract and sync with each other now maintain a normal heart rate and making sure the ventricles contract at the same time now that's all working towards maximizing circulation because if the heart's going to slowly it won't circulate blood to the body fast enough and likewise if the heart's pumping too quickly there's not enough time for the ventricles to fill with blood and therefore the heart won't pump enough blood to the rest of the body so pacemakers typically consist of two parts the first part is the pulse generator which consists of a battery and the battery is what supplies power to the device and supplies energy for the electro signal to the heart and the other part is the control center which is kind of like the brains of the face maker the second main part of the pacemakers are the electrodes now the electrodes are basically wires that run from the pulse generator to the heart so again electrodes are wires that run from the pulse generator to the heart we're going to talk about four different types of pacemakers so the first type is the external pacemaker also known as transcutaneous now trans means through and cutaneous refers to the skin so this means through the skin now in an external pacemaker the pulse generator is on the outside of the body and the wires are connected to these big pads that stick to the skin so we have wires are connecting to these sticky pads that are just connected to the skin there's nothing on the inside and the electrical signal goes through the skin or transcutaneous external Pacers are used in emergency situations as in code situations when the heart stops this is because in emergencies you need to act fast and the fastest way to pay someone is to just stick these two pads onto the skin and paste them the second Pacer room talk about is the temporary epicardial pacemaker now epicardial refers to the epicardium which is the outermost layer of the heart I'm highlighting in green right here that's the epicardium in the temporary epicardial pacemaker you have the pulse generator on the outside of the body and the wires are actually connected to the epicardium or the outermost layer of the heart and the wires will have to come out someplace on the chest wall so temporary epicardial Pacers are usually placed during heart surgery now why would you have this place during heart surgery well heart surgery is a pretty invasive procedure and you effectively have a lot of trauma at the heart and the tissue around the heart so you're going to get a lot of inflammation of the tissue at and around the heart now the inflammation can temporarily irritate heart tissue and this puts people at risk for having and I'm normally slow heart rate or bradycardia so the surgeon because they might be concerned about the patient having bradycardia can insert a temporary epicardial pacemaker during surgery typically these temporary epicardial Pacers will remain in the heart until several days after the surgery okay so the next type of pace we're going to talk about is a temporary endocardial pacer now endocardial refers to the endocardium which is the innermost layer of the heart and I'm not lighting that in black here so the endocardial pacer refers to the endocardium the innermost lining of the heart and in temporary endocardial pacer the pulse generator is located on the outside of the body and the wires are implanted into the body be a large vein usually in the neck such as the subclavian or the right internal jugular so the wires go through a large vein in the neck they're guided down to the right either the right atrium or the right ventricle and then from there they make contact with the endocardium temporary endocardial patients are also known as transvenous pacing in trans means through and venous refers to the veins so this pacer goes through the veins and gets down to the heart either to the HM of the ventricle and then makes contact with the endocardium now when do you use temporary endocardial Pacers you use Montana there's some sort of temporary heart rate abnormality that should resolve over time for example there could be drug-induced bradycardia or slow heart rate because of drugs or medications or if someone gets whacked on the chest really hard that can cause some chest trauma and AV nodal irritation which can cause the heart to beat at a slow rate both of these resolve with time so you don't need a permanent pacemaker a temporary one will suffice until the heart rate comes back to normal you can also use a temporary endocardial pacer while you're waiting for a permanent pacer so say someone comes in at night and needs a permanent pacemaker but that / - pacemaker can't be placed until the morning well they can have a temporary pacer place overnight until morning when they can have the permanent pacemaker placed which brings us the last pacemaker we talk about the permanent pacemaker so the permanent pacemaker is one where everything's internal someone write that here just so remember that everything is internal the pulse generator you tucked away underneath subcutaneous tissue or even muscle and the wires are guided through the venous system into the heart it looks a lot like the temporary endocardial pacer except the pulse generator is tucked inside the body everything's internal now when do you need a permanent pacemaker well in certain cases of heart block such as third-degree heart block or advanced second-degree heart block pastries are also indicated for certain people with symptomatic sinus bradycardia now what does that mean that means at baseline this patient has a slow heart rate and a slow heart rate is actually causing symptoms such as fatigue or lightheadedness or passing out now does everybody with a slow heart rate need a pacemaker not exactly there's definitely people in the population such as young athletes they have a really slow resting heart rate but they have a strong young heart that can compensate and still perfuse the body even with a slow heart rate these permanent pacemakers are good for people who have symptomatic bradycardia meaning that they have symptoms accompanying their slow heart rate and these symptoms indicate that they're not circulating blood adequately to the rest of the body which is why they might feel fatigued or lightheaded